The Forkhead box transcription factor (FOX) family plays an essential role in embryogenesis, especially during brain development. Our hypothesis is that de-regulation of FOX genes may contribute to aggressive tumor biology and therapy resistance in patients with glioblastoma multiforme (GBM). Univariate and multivariate analyses were performed to evaluate prognostic significance of transcript levels of 31 FOX genes in a test set of GBM patients (n=191) and validated them in The Cancer Genome Atlas (TCGA) cohort comprising of 508 adult cases of GBM. The predictive significance of key FOX genes was investigated in patients who received chemotherapy or radiotherapy. Low FOXA2 mRNA, low FOXN2 mRNA, low FOXN3 mRNA and high FOXG1 mRNA were associated with poor survival in the test and TCGA validation cohorts. In multivariate analysis, low FOXA2 mRNA, low FOXN2 mRNA, low FOXN3 mRNA and high FOXG1 mRNA remained independently associated with poor survival in the test and TCGA validation cohorts. In patients who received chemotherapy or radiotherapy, low FOXA2 mRNA, low FOXN2 mRNA and high FOXG1 mRNA correlated with adverse outcomes in the TCGA validation cohort. To our knowledge, our data provide the first comprehensive clinical evidence that FOXA2, FOXN2, FOXN3 and FOXG1 are promising biomarkers of GBM and warrant further investigation.